versión On-line ISSN 1678-4499

Resumen

Pomelo, one of the main early persimmon selection developed in the breeding program of the Instituto Agronômico, Campinas, State of São Paulo, Brazil, tends to be alternate bearing, that is the trees tend to yield a high production in one year followed by a low or no production in the next year. This tendency continues in the suceessive years unless some external factor may influence the natural set of flower buds. To obtain more information about the alternate bearing habit of Pomelo, anual yields were registered for each individual plant in 54 trees of this variety, at Campinas Experimental Center, during ten successive years (1971/80). It was distinguished three types of plant behaviour: group A - 26 trees that bore moderate to heavy productions in the odd years and low or no production in the even years; group B - 22 trees that yielded alternatively also, but in an opposite year sequence; group C - six remaining trees showing a moderate alternate bearing habit, in which the successive yields were located alternatively on different branches of the tree. So, it was not possible to select any tree that did not show a type of alternate bearing habit, although the ten year average yield of the plot was high: 61.4kg of fruit per tree, weighing 126g per fruit. An early fruit thinning made in November 1976, pulling off about 50% of the young fruits of the trees from groups A and C, resulted in a regular yield of large fruits in 1977, averaging 57.9kg of persimmons per tree weighing 199g per fruit, followed by the heaviest yield of the plot in 1978:148.2kg of fruit per tree weighing 123g per fruit. The results indicated there is a possibility of breaking the alternate bearing habit of Pomelo persimmon, and of improving its yield quality and size, through a strong thining of young fruits on the most prolific trees when a large crop is being borne.